Espalier – Two-Dimensional
Pruning for Trees and Shrubs
Marianne C. Ophardt
Washington State University Cooperative Extension
Area Extension Agent
Trees and shrubs
are part of our three dimensional world.
It takes an adventuresome gardener to turn a three dimensional plant
into one with only two dimensions. Espalier
is the art of pruning that involves controlling tree and shrub growth in a
single plane... with the support of a building wall, fence, or trellis.
This type of pruning is an ancient art that dates back to Roman times
and was later refined by medieval Europeans to save space in the walled
gardens around castles, cathedrals, and monasteries.
They were able to reduce the space needed to grow fruit by keeping the
growth relatively flat against garden walls... leaving open space for other
garden crops.
Espaliering also
proved useful in cooler climates with shorter growing seasons.
By espaliering fruit trees against south and west facing walls, early
gardeners found that they could take advantage of the extra heat in these
situations, producing fruit in areas where their climate was usually a little
too short or too cool to produce fruit. These
south and west facing sites warmed up earlier in the spring and stayed warmer
later in the season.
Another advantage
to using espalier techniques with fruit trees was the effect espaliering had
on the trees. Espaliered fruit
trees usually come into bearing at an earlier age and are generally more
productive with deeper fruit color. This
is because of branch angles and the increased light penetration to leaf
surfaces that result from the single plane.
The technique of
espalier pruning is practiced by some commercial orchardists today because of
the early bearing and productiveness of espaliered trees.
Home gardeners and landscapers often practice espalier pruning for its
decorative potential. Using
espalier techniques, gardeners can create screens that don’t take up much
room and have a softer look than fences or brick walls.
Espaliered plants can also provide decoration for large, monotonous
windowless building walls.
Gardeners should
take note that espaliering is a technique that takes time and some expense.
You must select the right type of plants and the right site along with
making sure you have adequate support for the plant.
Espaliering a tree or shrub involves pruning and training over time to
develop and maintain the framework.
Let’s first
chat about what types of plants lend themselves well to the art of espalier.
Typically you want plants that have long, flexible branches.
Plants with short or stiff branches are hard to train.
You should also consider the mature height of the tree or shrub.
A tree or shrub, whose mature height is much greater than the wall,
fence, or structure you plan to train it too, will be unsuitable.
Favored shrubs for espalier include cotoneaster, forsythia, holly,
Pfitzer juniper, Kousa dogwood, pyracantha,
winged euonymus, flowering quince, star magnolia, and viburnum. Favored trees
for espalier include apple, crabapple, and pear.
Fruit trees that bear their fruit on long-lived spurs are the easiest
to espalier. Fruit varieties that
have predominantly spur-type growth, such as Red Delicious, Golden Delicious,
and Braeburn apple varieties along with Bartlett pears, work the best.
In selecting a
plant, pick a young, vigorous tree or shrub that has a few well-balanced limbs
off the main trunk. Wait until
after the plant becomes well established before you perform the extensive
pruning needed to start your espalier framework.
In some nurseries you might be able to find plants that already have
some initial espalier training. This will make getting started easier.
When planting
your tree, be sure to plant it properly to help insure a tree with a healthy
root system. If you’re planting
your tree or shrub against a solid wall, the plant should be situated about
six to ten inches away from the wall to allow for air circulation behind the
plant.
You will need to
provide a sturdy support on which to develop your plant’s framework.
This can be done by stringing heavy wire of at least 12 to15 gauge from
eye bolts on the fence or wall. You
can also develop your espalier on a free standing trellis.
Just be sure that the trellis is sturdy enough to support the weight of
both branches and potential fruit. When
making a trellis for fruit trees, use 4x4 pressure treated posts, sinking the
posts two feet into the soil. Set
the posts about ten feet apart, securing the end posts with stakes and guy
wires. With fruit trees you’ll probably want two to three levels
of wire with the bottom wire situated about 18 inches from the ground.
Designing your
espalier is the fun part. A well designed and trained espalier is a real work
of art. If you’re doing your
first espalier, you should probably start with a simple design. Some of the
most common designs are fan-shaped, T-shaped, palmate, pinnate, chevron or
V-shaped. More difficult designs
are cordon, basket weave, and candelabra.
Check pruning books in your local library for diagrams of these
designs. With many of these
designs, you’ll need to pattern your wire supports accordingly.
If you want something less formal, an asymmetrical informal espalier
can be created by allowing the plant to grow and dictate the design.
Training in this case only consists of keeping growth in one plane.
After your tree
or shrub is planted and you have its supports in place, you’ll begin its
training. Spread the main
branches onto the supports and tie them in place. You need to be careful not
to crack or break branches when you bend them into the wanted position.
New growth early in the summer will be more flexible than older
branches.
When tying down
the branches, use soft string, strips of rags, rubber grafting bands, plant
ties, or raffia. Avoid using wire
that can cut into the bark. Tie
the branches to the supports loosely, leaving some extra room for the branch
to grow. Check the ties every
three or four months to be sure they aren’t restricting or damaging the
branches. Replace the tie if its
hampering growth.
Branches that
aren’t part of the design should be pruned off the spring after planting.
Shape the plant every month or so, removing branches or twigs that aren’t in
the correct plane of growth. Training
of simple designs may take only two or three years to develop, but more
intricate designs will take longer to achieve.